Ice maker evaporator

ABSTRACT

An ice maker evaporator includes a plurality of dividers and one or more micro-multi-port tubes that are arranged into a plurality of cells such that ice cubes can be formed therein. The evaporator can be made of aluminum and the components can be brazed, soldered or otherwise joined together.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No. 61/011,209, filed on Jan. 15, 2008. The entire disclosure of the above application is incorporated herein by reference.

FIELD

The present disclosure relates to ice makers and, more particularly, to evaporators for use in ice makers.

BACKGROUND AND SUMMARY

The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.

As is known, ice makers typically form ice by recirculating water over an evaporator cooled with refrigerant supplied by a refrigerant system. The evaporator is typically oriented vertically, in a grid layout, and water is continuously run over the surface and consequently building up ice. When the ice reaches a desired thickness, the refrigeration cycle is reversed thereby heating a portion of the ice. When the boundary of the ice melts, the ice cubes fall from the grid into a bin under the force of gravity.

Conventional ice maker evaporators are made from copper, however the evaporator may be nickel plated for production of ice to be used for consumption in light of health reasons. Such conventional evaporators can include a back plate, vertical dividers, and horizontal dividers that collectively form a grid pattern. A continuous round copper tube can be bent into a serpentine configuration and applied to the grid for cooling. The entire assembly can be brazed or soldered together.

However, it should be appreciated that conventional evaporators suffer from a number of disadvantages. Copper is a high cost material and thus adds significantly to the overall cost of production. This production cost is further exacerbated by the need for nickel plating the copper in applications intended to produce ice for consumption. Nickel plating is also known to produce byproducts that must be carefully handled and disposed of to avoid environmental and health issues.

Furthermore, it should be appreciated that the copper tube used on conventional evaporators that carries the refrigerant is not in direct contact with the ice being formed. Rather, the tube is attached to the backside of the back plate so that heat is drawn from the water through the plate and into the refrigerant within the tube. As a result, the contact resistances between the parts of the evaporator degrade the overall performance of the evaporator and of the ice maker. Additionally, the copper has a high thermal mass and thus requires additional energy usage during the heating and cooling of every harvest cycle. Moreover, this type of conventional evaporator can only produce ice on a single side thus limiting the capacity of the evaporator. Still further, as refrigeration technology changes, it is expected that ice makers will use CO₂ for the refrigerant. Round copper tube is difficult to use with CO₂ because of the very high pressures involved in a CO₂ refrigeration cycle. Therefore, there is a need to overcome these disadvantages.

In accordance with the present disclosure, an ice maker evaporator is provided having a plurality of dividers and a plurality of micro-multi-port tubes. The micro-multi-port tubes are in fluid communication with a supply header and a return header. The dividers and micro-multi-port tubes are arranged into a plurality of cells such that ice cubes can be formed therein. In accordance with another aspect of the present disclosure, an ice maker evaporator is provided having a plurality of dividers defining a plurality of openings therein. At least one micro-multi-port tube in a serpentine configuration extends through multiple openings in the dividers. A supply header and a return header are in fluid communication with at least one micro-multi-port tube. The dividers and the micro-multi-port tube form a plurality of cells such that ice cubes can be formed therein.

The evaporator of the present disclosure is advantageous over conventional evaporators in that the refrigerant carrying tubing (i.e. the micro-multi-port tube(s)) can be in direct contact with the ice being formed thereby advantageously reducing the contact resistance and the variety of materials through which heat must be conducted to form the ice. Moreover, the use of aluminum provides a lower cost alternative to the use of the copper having nickel plating. The evaporator can also advantageously be lighter in weight and require less energy to cool or heat thereby improving the performance. Moreover, a coating may not be required with the aluminum components. If a coating is desired, however, several environmentally friendly, economical coatings are commercially available. Moreover, in some embodiments, it is possible to produce ice on both sides of the evaporator thereby improving the capacity of the evaporator for a given space. Additionally, micro-multi-port tubing can withstand high pressures and can be used with a CO₂ refrigerant system.

Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.

DRAWINGS

The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.

FIG. 1 is an enlarged fragmented perspective view of a portion of a micro-multi-port tube according to the present disclosure;

FIG. 2 is a perspective view of the first embodiment of an evaporator according to the present disclosure;

FIG. 3 is a front plan view of the evaporator of FIG. 2;

FIG. 4 is a cross-sectional view along line 4-4 of FIG. 3;

FIG. 5 is a cross-sectional view similar to that of FIG. 4 showing an alternate to the first embodiment wherein ice cubes can be made on both sides of the evaporator;

FIG. 6 is a perspective view of a second embodiment of an evaporator according to the present disclosure;

FIG. 7 is a front plan view of the evaporator on FIG. 6;

FIG. 8 is a cross-sectional view along line 8-8 of FIG. 7;

FIG. 9 is a perspective view of an alternate to the second embodiment according to the present disclosure wherein ice cubes can be formed on both sides of the evaporator;

FIG. 10 is a front plan view of the evaporator of FIG. 9;

FIG. 11 is a cross-sectional view along line 11-11 of FIG. 10;

FIG. 12 is a perspective view of a third embodiment of an evaporator according to the present disclosure;

FIG. 13 is a front plan view of the evaporator of FIG. 12; and

FIG. 14 is a cross-sectional view along line 14-14 of FIG. 13.

DETAILED DESCRIPTION

The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. It should be understood that throughout the drawings, corresponding reference numerals (e.g. 20, 120, 220, etc. and 20, 20′, 20″, etc.) indicate like or corresponding parts and features.

Referring to FIG. 1, a micro-multi-port (“MMP”) tube that can be used in an evaporator of the present invention is shown. MMP tube 20 has opposite first and second heat transfer surfaces 22, 24 and side walls 26 extending therebetween. First and second heat transfer surfaces 22, 24 are the primary heat transfer surfaces and have significantly more surface area than side walls 26. MMP tube 20 can have a plurality of internal passageways 28 that extend along the length of MMP tube 20. Each passageway 28 can be hydraulically discreet and separated by walls 30. Passageways 28 can be hydraulically parallel. As seen, passageways 32 that are adjacent side walls 26 can be slightly larger than central passageways 34. Passageways 32 that are adjacent side walls 26 can take a variety of forms and shapes that provide for ease of manufacture and efficient heat transfer along side walls 26 and can be different than central passageways 34.

The hydraulic diameter of each passageway 28 can be smaller than that of typical tubing used in refrigeration systems and, as a result, can have a much greater conductive heat transfer co-efficient. MMP tube 20 is typically extruded, as is known in the art. The extrusion process can yield a flattened tube that is continuous and seamless. The MMP tube 20 can be cut to any desired length. MMP tube 20 can be aluminum.

Referring now to FIGS. 2-4, an evaporator 40 according to the first embodiment is shown. Evaporator 40 includes a grid 42 wherein ice cubes are formed. Supply and returned headers 42, 46 are attached to opposite ends of grid 42. Headers 44, 46 are operable to supply a refrigerant flow through grid 42. In some embodiments, at least supply header 42 can comprising internal baffles to direct refrigerant into one or more discrete internal passageways 28 of MMP tubes 20, thereby forming discrete hydraulic circuits therein. The internal baffles can comprise a round disc placed within the header to block the flow between MMP circuits. Grid 42 includes a plurality of MMP tubes 20 and a plurality of dividers 48. Dividers 48 can extend generally vertically while MMP tubes 20 can extend horizontally. Dividers 48 can include a plurality of aligned openings through which MMP tubes 20 can extend. Dividers 48 are in heat-transferring relation with MMP tubes 20. Grid 42 has a front side 50 and a backside 52. An aluminum back plate 54 can extend along backside 52 of grid 42. MMP tubes 20, dividers 48 and back plate 54 can form a plurality of cells 56 within grid 42 in which ice cubes are formed. In some embodiments, pressure relief holes can be formed within back plate 54 in communication with one or more of the plurality of cells 56. Such pressure relief holes can serve to relieve vacuum pressure that may form within each cell 56 during cube harvesting that may restrict the cubes from freely falling from the respective cell. MMP tubes 20 can be canted relative to horizontal, as shown in FIG. 4, to facilitate the removal of ice cubes formed within cells 56. That is, MMP tubes 20 can have a cant angle ∝ such that during the ice cube harvesting operation, the ice cubes formed within cells 56 will tend to fall out of cells 56 due to gravity.

MMP tubes 20 can be attached to headers 44, 46 such that a refrigerant flowing through headers 44, 46 also flows through passageways 28 within MMP tubes 20. Headers 44, 46 and MMP tubes 20, dividers 48 and back plate 54 can all be brazed, soldered or otherwise joined together in heat-transferring relation and form evaporator 40. Headers 44, 46 can be aluminum and can have round aluminum tubing 58 brazed, soldered or otherwise joined thereto to connect headers 44, 46 to the refrigeration system within which evaporator 40 is to be utilized. Tubes 58 can transition from aluminum to copper, if desired. The spacing of MMP tubes 20 and dividers 48 can be selected to produce ice cubes within cells 56 of the desired shape and size.

Thus, in evaporator 40, refrigerant can be supplied to supply header 44 and flow through MMP tubes 20 and exit return header 46. As such, ice cubes being formed within cells 56 are in direct contact with MMP tubes 20 thereby providing a short heat-transfer flow path. Moreover, with dividers 48 and back plate 54 also in heat-transferring relation with MMP tubes 20, additional heat-transfer paths are formed.

Referring now to FIG. 5, an alternate configuration of evaporator 40′ is shown. In this configuration, evaporator 40′ includes a first grid 42′ and a second grid 62′. Grids 42′, 62′ are on opposite sides of back plate 54′. Grid 62′ is essentially the same as grid 42′. MMP tubes 20′ in first grid 42′ and in second grid 62′ can be in fluid communication with the same supply and return headers. Alternatively, separate supply and return headers can independently supply and return refrigerant through MMP tubes 20′ in each grid 42′, 62′. Thus, in evaporator 40′, twice as many cells 56′ can be formed with a small increase in the size of evaporator 40′.

Referring now to FIGS. 6-8, an evaporator 140 according to a second embodiment of the present disclosure is shown. Evaporator 140 utilizes a single MMP tube 120 that is arranged in a serpentine configuration. Grid 142 is formed by MMP tube 120 extending horizontally from one end to the other and then curving 180° to head back to the previous end. The horizontal sections of MMP tube 120 extend through vertical dividers 148. Ends of MMP tube 120 can be connected in fluid-communication with supply header 144 and return header 146. Headers 144, 146, MMP tube 120, dividers 148 and back plate 154 can be brazed, soldered or otherwise joined together and can be in heat-transferring relation.

Referring now to FIGS. 9-11, an alternate configuration of an evaporator 140′ of the second embodiment is shown. Evaporator 140′ includes first and second grids 142′, 162′ that are disposed on opposite sides of back plate 154′. A first set of supply and return headers 144′, 146′ supplies refrigerant through MMP tube 120′ associated with grid 142′. A second set of supply and return headers 166′, 168′ are in fluid-communication with the MMP tube 120′ associated with second grid 162′ to supply a flow of refrigerant therethrough. The MMP tubes 120′ in first and second grids 142′, 162′ can be canted as shown to reflect the force of gravity pulling ice cubes from cells 156′ therein.

Referring now to FIGS. 12-14, an evaporator 230 according to a third embodiment of the present disclosure is shown. In evaporator 230, grid 242 is formed by a plurality of vertically extending MMP tubes 220 and a plurality of horizontally extending dividers 272. In this embodiment, MMP tubes 220 extend vertically in a wavy or sinuous fashion, as shown in FIG. 14, and do not extend through dividers 272. Rather, dividers 272 can be solid and can extend along side walls 226 of MMP tubes 220. Valleys 274, 276 can be formed by MMP tubes 220 on opposite sides thereof. Cells 256 can be formed in each valley 274, 276 between dividers 272. As a result, evaporator 240 can have first and second grids 242, 262 on opposite sides thereof. MMP tubes 220 can extend between supply and return headers 244, 246 in fluid-communication therewith to enable a refrigerant to flow therethrough. MMP 220, headers 244, 246 and dividers 272 can be brazed, soldered or otherwise joined together. In evaporator 240, a back plate is not needed.

In some of the embodiments of the present disclosure, the MMP tube is canted at angle ∝ relative to horizontal. The canting facilitates the removal of ice cubes formed in the cells via gravity. The value of angle ∝ can vary depending upon the particular design. In some embodiments, angle ∝ can be about 15°.

The evaporator according to the present disclosure can be constructed of aluminum to provide a lower material cost. Additionally, the MMP tube can be in direct contact with the ice being formed within the cells thereby improving the performance and advantageously reducing the contact resistance for heat-transfer therein. As a result, less energy is required to cool and heat the evaporator to form the ice cubes and remove them therefrom, thereby improving performance. Moreover, because the MMP tube is integrated into the grid, separate grids can be formed on each side of a back plate thereby allowing ice to be made on both sides of the evaporator. Moreover, the use of MMP tubes is advantageous in that the MMP tubes can withstand high pressures and can be used with a CO₂ refrigeration system.

While the present disclosure has been described by reference to specific examples, it should be appreciated that these embodiments are merely exemplary and that changes can be made to these embodiments. For example, the entire evaporator may be plated for corrosion and sanitary purposes. For example, the aluminum evaporator can be anodized. Additionally, a polymeric coating, such as Teflon®, can also be used if desired. Additionally, it should be appreciated that additional MMP tubing can be brazed, soldered or otherwise joined to the back plate of the evaporator to provide additional cooling and heating to facilitate the formation of ice cubes and the removal of the ice cubes. Moreover, in some embodiments the dividers, MMP tube and/or back plate can be held together mechanically in addition to or in lieu of brazing or soldering. Thus, the above description of the present disclosure is merely exemplary in nature and variations that do not depart from the gist of the disclosure are intended to be within the scope of the disclosure. Such variations are not to be regarded as a departure from the spirit and scope of the present disclosure. 

1. An ice maker evaporator comprising: a plurality of dividers; a plurality of micro-multi-port tubes; a supply header in fluid communication with said plurality of micro-multi-port tubes; and a return header in fluid communication with said plurality of micro-multi-port tubes, wherein said plurality of dividers and said plurality of micro-multi-port tubes are arranged into a plurality of cells such that ice cubes can be formed therein.
 2. The ice maker evaporator of claim 1, wherein said plurality of micro-multi-port tubes and said plurality of dividers are aluminum.
 3. The ice maker evaporator of claim 1, wherein said plurality of micro-multi-port tubes are sinuous and a plurality of valleys are formed on opposing sides of said plurality of micro-multi-port tubes, and said plurality of dividers separate said plurality of micro-multi-port tubes from one another.
 4. The ice maker evaporator of claim 3, wherein said plurality of dividers extend in a same direction as said plurality of micro-multi-port tubes.
 5. The ice maker evaporator of claim 1, wherein said plurality of micro-multi-port tubes are canted relative to a horizontal axis.
 6. The ice maker evaporator of claim 1, further comprising a back plate.
 7. The ice maker evaporator of claim 6, wherein said plurality of dividers and said plurality of micro-multi-port tubes are arranged on opposing sides of said back plate and form two grids with a plurality of ice cube forming cells therein.
 8. The ice maker evaporator of claim 1, wherein each of said plurality of micro-multi-port tubes has a plurality of hydraulically discrete flow passageways extending therethrough.
 9. The ice maker evaporator of claim 1, wherein said plurality of dividers, said plurality of micro-multi-port tubes and said supply and return headers are brazed together.
 10. The ice maker evaporator of claim 1, wherein said plurality of dividers, said plurality of micro-multi-port tubes and said supply and return headers are soldered together.
 11. The ice maker evaporator of claim 1, wherein said plurality of dividers, said plurality of micro-multi-port tubes and said supply and return headers are joined together in heat-transferring relation.
 12. The ice maker evaporator of claim 1, wherein at least one of said supply and return headers contain internal baffles to divide the plurality of micro-multi port tubes into separate hydraulic circuits.
 13. The ice maker evaporator of claim 1, wherein said plurality of dividers contain pressure relief holes to allow pressure behind the ice to equalize and improve harvest.
 14. The ice maker evaporator of claim 1, wherein at least one of said supply and return headers is transitioned to round copper tube.
 15. An ice maker evaporator comprising: a plurality of dividers having a plurality of openings therein; at least one micro-multi-port tube in a serpentine configuration, said at least one micro-multi-port tube extending through multiple openings in said plurality of dividers; a supply header in fluid communication with said at least one micro-multi-port tube; and a return header in fluid communication with said at least one micro-multi-port tube, wherein said plurality of dividers and said at least one micro-multi-port tube form a plurality of cells such that ice cubes can be formed therein.
 16. The ice maker evaporator of claim 15, wherein said plurality of dividers and said at least one micro-multi-port tube are aluminum.
 17. The ice maker evaporator of claim 15, further comprising a back plate attached to said at least one micro-multi-port tube and said plurality of dividers and forming a portion of said cells, and wherein said at least one micro-multi-port tube is at least two micro-multi-port tubes, said at least two micro-multi-port tubes being disposed on opposite sides of said back plate such that a grid of ice cube forming cells are formed on each side of said back plate.
 18. The ice maker evaporator of claim 17, wherein each of said at least two micro-multi-port tubes are in fluid communication with different supply and return headers.
 19. The ice maker evaporator of claim 15, wherein said at least one micro-multi-port tube is canted relative to a horizontal axis.
 20. The ice maker evaporator of claim 15, wherein said at least one micro-multi-port tube has a plurality of hydraulically discrete flow passageways extending therethrough.
 21. The ice maker evaporator of claim 15, wherein said plurality of dividers, said at least one micro-multi-port tube and said supply and return headers are brazed together.
 22. The ice maker evaporator of claim 15, wherein said plurality of dividers, said at least one micro-multi-port tube and said supply and return headers are soldered together.
 23. The ice maker evaporator of claim 15, wherein said plurality of dividers, said at least one micro-multi-port tube and said supply and return headers are joined together in heat-transferring relation.
 24. The ice maker evaporator of claim 15, wherein said plurality of dividers contain pressure relief holes to allow pressure behind the ice to equalize and improve harvest.
 25. The ice maker evaporator of claim 12, wherein at least one of said supply and return headers is transitioned to round copper tube. 